The versatile Twin Top allows you to use these twin sections independently or together for a total coverage of 8'W x 17.5'L. Both sections fold up and store in matching storage boots when not in use. The top is constructed of SurLast 100% polyester fabric with 1" sq. anodized aluminum tubing. SurLast is designed for ease of use and flexibility. It has a urethane coating that adds to its stability by making it highly water-resistant as well as shrink and stretch-resistant. This durable UV-resistant fabric provides excellent strength against tears and abrasions and comes with a 4-year warranty.